The long term forecast in the table above contains the most predictable weather information, and how certain we are that the forecast is correct.

The probability forecast in the diagram below indicates the probabilities for different possible developments of the temperature and precipitation. The long term forecast is given by black lines.

The grey fields (for temperature) and the blue fields (for precipitation) indicate the range of possible weather developments which are predominantly probable (80 percent). The width of the fields is proportional to the degree of uncertainty of the forecast.

Within these fields, it is considered most probable (50 percent) that the development hits the dark part. Still it is somewhat probable (30 percent) that it hits the lighter part outside the dark.